A study on the bonding strength of co-cured T800/epoxy composite-aluminum single-lap joint under out-of-plane compressive pressure condition

Abstract

In this paper, the bonding strengths of co-cured T800 carbon/epoxy composite-aluminum single-lap joints with and without additional pressures in the out-of-plane direction were investigated to simulate the stress condition at the interface between the composite layers and the aluminum liner of a Type III pressure vessel made by the filament winding process. All test specimens were fabricated by autoclave vacuum bag de-gassing molding under controlled forming pressures (absolute pressures of 0.1, 0.3, and 0.7 MPa including vacuum). A special device which can impose uniform additional pressures on the bonding part of the single-lap joint specimen was designed. Additional pressures were applied and, subsequently, the bonding strengths of the composite-aluminum single-lap joint specimen were estimated. After the three different additional pressures (absolute pressures of 0.1, 0.3, and 0.7 MPa) were applied to each of the specimens, the effects of the additional pressures on the bonding strengths of the co-cured single-lap joints were evaluated.